| Message ID | 1461084994-2355-9-git-send-email-eric.auger@linaro.org |
|---|---|
| State | New |
| Headers | show |
Hi Robin, On 04/20/2016 07:19 PM, Robin Murphy wrote: > On 19/04/16 17:56, Eric Auger wrote: >> This function checks whether >> - the device emitting the MSI belongs to a non default iommu domain >> - the iommu domain requires the MSI address to be mapped. >> >> If those conditions are met, the function returns the iommu domain >> to be used for mapping the MSI doorbell; else it returns NULL. >> >> Signed-off-by: Eric Auger <eric.auger@linaro.org> >> --- >> drivers/iommu/dma-reserved-iommu.c | 19 +++++++++++++++++++ >> include/linux/dma-reserved-iommu.h | 18 ++++++++++++++++++ >> 2 files changed, 37 insertions(+) >> >> diff --git a/drivers/iommu/dma-reserved-iommu.c >> b/drivers/iommu/dma-reserved-iommu.c >> index 2522235..907a17f 100644 >> --- a/drivers/iommu/dma-reserved-iommu.c >> +++ b/drivers/iommu/dma-reserved-iommu.c >> @@ -17,6 +17,7 @@ >> >> #include <linux/iommu.h> >> #include <linux/iova.h> >> +#include <linux/msi.h> >> >> struct reserved_iova_domain { >> struct iova_domain *iovad; >> @@ -332,3 +333,21 @@ unlock: >> } >> EXPORT_SYMBOL_GPL(iommu_put_reserved_iova); >> >> +struct iommu_domain *iommu_msi_mapping_desc_to_domain(struct msi_desc >> *desc) >> +{ >> + struct device *dev; >> + struct iommu_domain *d; >> + >> + dev = msi_desc_to_dev(desc); >> + >> + d = iommu_get_domain_for_dev(dev); >> + >> + if (!d || (d->type == IOMMU_DOMAIN_DMA)) >> + return NULL; >> + >> + if (iommu_domain_get_attr(d, DOMAIN_ATTR_MSI_MAPPING, NULL)) >> + return NULL; > > Yeah, I don't see why we couldn't just use > > if (domain->ops->capable(IOMMU_CAP_INTR_REMAP)) > return NULL I don't think this works. This will lead to MSI iommu mapping on x86 when irq_remapping is disabled. To be further checked though. Eric > > there instead. > >> + >> + return d; >> +} >> +EXPORT_SYMBOL_GPL(iommu_msi_mapping_desc_to_domain); >> diff --git a/include/linux/dma-reserved-iommu.h >> b/include/linux/dma-reserved-iommu.h >> index 8722131..8373929 100644 >> --- a/include/linux/dma-reserved-iommu.h >> +++ b/include/linux/dma-reserved-iommu.h >> @@ -19,6 +19,7 @@ >> #include <linux/kernel.h> >> >> struct iommu_domain; >> +struct msi_desc; >> >> #ifdef CONFIG_IOMMU_DMA_RESERVED >> >> @@ -70,6 +71,17 @@ int iommu_get_reserved_iova(struct iommu_domain >> *domain, >> * if the binding ref count is null, destroy the reserved mapping >> */ >> void iommu_put_reserved_iova(struct iommu_domain *domain, >> phys_addr_t addr); >> + >> +/** >> + * iommu_msi_mapping_desc_to_domain: in case the MSI originates from >> a device >> + * upstream to an IOMMU and this IOMMU translates the MSI transaction, >> + * this function returns the iommu domain the MSI doorbell address >> must be >> + * mapped in. Else it returns NULL. >> + * >> + * @desc: msi desc handle >> + */ >> +struct iommu_domain *iommu_msi_mapping_desc_to_domain(struct msi_desc >> *desc); >> + >> #else >> >> static inline int >> @@ -93,5 +105,11 @@ static inline int iommu_get_reserved_iova(struct >> iommu_domain *domain, >> static inline void iommu_put_reserved_iova(struct iommu_domain *domain, >> phys_addr_t addr) {} >> >> +static inline struct iommu_domain * >> +iommu_msi_mapping_desc_to_domain(struct msi_desc *desc) >> +{ >> + return NULL; >> +} >> + >> #endif /* CONFIG_IOMMU_DMA_RESERVED */ >> #endif /* __DMA_RESERVED_IOMMU_H */ >> >
diff --git a/drivers/iommu/dma-reserved-iommu.c b/drivers/iommu/dma-reserved-iommu.c index 2522235..907a17f 100644 --- a/drivers/iommu/dma-reserved-iommu.c +++ b/drivers/iommu/dma-reserved-iommu.c @@ -17,6 +17,7 @@ #include <linux/iommu.h> #include <linux/iova.h> +#include <linux/msi.h> struct reserved_iova_domain { struct iova_domain *iovad; @@ -332,3 +333,21 @@ unlock: } EXPORT_SYMBOL_GPL(iommu_put_reserved_iova); +struct iommu_domain *iommu_msi_mapping_desc_to_domain(struct msi_desc *desc) +{ + struct device *dev; + struct iommu_domain *d; + + dev = msi_desc_to_dev(desc); + + d = iommu_get_domain_for_dev(dev); + + if (!d || (d->type == IOMMU_DOMAIN_DMA)) + return NULL; + + if (iommu_domain_get_attr(d, DOMAIN_ATTR_MSI_MAPPING, NULL)) + return NULL; + + return d; +} +EXPORT_SYMBOL_GPL(iommu_msi_mapping_desc_to_domain); diff --git a/include/linux/dma-reserved-iommu.h b/include/linux/dma-reserved-iommu.h index 8722131..8373929 100644 --- a/include/linux/dma-reserved-iommu.h +++ b/include/linux/dma-reserved-iommu.h @@ -19,6 +19,7 @@ #include <linux/kernel.h> struct iommu_domain; +struct msi_desc; #ifdef CONFIG_IOMMU_DMA_RESERVED @@ -70,6 +71,17 @@ int iommu_get_reserved_iova(struct iommu_domain *domain, * if the binding ref count is null, destroy the reserved mapping */ void iommu_put_reserved_iova(struct iommu_domain *domain, phys_addr_t addr); + +/** + * iommu_msi_mapping_desc_to_domain: in case the MSI originates from a device + * upstream to an IOMMU and this IOMMU translates the MSI transaction, + * this function returns the iommu domain the MSI doorbell address must be + * mapped in. Else it returns NULL. + * + * @desc: msi desc handle + */ +struct iommu_domain *iommu_msi_mapping_desc_to_domain(struct msi_desc *desc); + #else static inline int @@ -93,5 +105,11 @@ static inline int iommu_get_reserved_iova(struct iommu_domain *domain, static inline void iommu_put_reserved_iova(struct iommu_domain *domain, phys_addr_t addr) {} +static inline struct iommu_domain * +iommu_msi_mapping_desc_to_domain(struct msi_desc *desc) +{ + return NULL; +} + #endif /* CONFIG_IOMMU_DMA_RESERVED */ #endif /* __DMA_RESERVED_IOMMU_H */
This function checks whether - the device emitting the MSI belongs to a non default iommu domain - the iommu domain requires the MSI address to be mapped. If those conditions are met, the function returns the iommu domain to be used for mapping the MSI doorbell; else it returns NULL. Signed-off-by: Eric Auger <eric.auger@linaro.org> --- drivers/iommu/dma-reserved-iommu.c | 19 +++++++++++++++++++ include/linux/dma-reserved-iommu.h | 18 ++++++++++++++++++ 2 files changed, 37 insertions(+) -- 1.9.1